So those ads, by failing to meet the statutory definition of "express advocacy," failed to trigger matching clean election funds for candidates Barbara Merrill and Pat LaMarche, exploiting a loophole in Maine's trailblazing, and laudable, clean election system.

Last year's hotly contested gubernatorial race was the stress test for clean election laws, and proved political money can find ways to circumvent campaign finance laws. The Legislature is considering several bills aimed at amending clean election laws.

Reviewing the system is smart, especially with the national attention it receives each time a similar campaign finance program is enacted, or defeated. The latest example is in the U.S. Senate, where the Fair Elections Now Act, based in part on Maine's system, has been introduced against the backdrop of the coming 2008 races.

Clean elections have been a rousing success in Maine, with more than 80 percent of legislative candidates in 2006 running publicly funded campaigns. This increased utilization now has lawmakers believing eligibility for public financing should be tightened, to avoid overtaxing the fund.

It's a fine idea. More stringent requirements would reinforce the need for candidates to generate widespread public support, and also reduce, or eliminate, the potential for sideshow campaigns - such as the recent gubernatorial bid by former Auburn Rep. John Michael - from siphoning needed public funds.

Maine enacted clean election laws in 1996 as a citizen's initiative and still holds an annual referendum on the program around this time each year. State income tax returns ask taxpayers if they wish to send $3 to the clean election fund; doing so neither increases taxes paid, nor decreases anticipated tax refunds.

It supports a program that's made campaign financing in Maine more transparent, and the aspiration of public service more attainable. Clean elections, however, need public support to thrive, and we urge every taxpayer filing today - the deadline for returns - to check the clean elections box.

And in return, we urge lawmakers to close clean election loopholes, as fast as they're discovered.